Re: Generic Modeling

> Based on the structure you presented...
> List the plant names of companies that have line units with the same type
> of equipment, provided that the cities where the plants are located are not
> in the same city and that the number of plant floors exceeds three.

I am assuming you are referring to one type of equipment and the equipment could be located anywhere below the level of a Complex (ie VortexEngComplex).

> List the results in a structure that is representative of company name, plant
> name, plant location, number of floors, and line units per floor."

The resulting objset would contain the matching objects in the original structure and does not return a new structure. Note, different companies may have different/missing levels.

> Is there a data access language or syntax that would allow a somewhat rapid
> construction of this query? Or would it involve a degree of hard-coding?

Simple queries can be contructed via graphical interface (www.xdb1.com/Basics/Query.asp). More complex queries, like the above, would require code.

> Would performance be degraded in terms of access paths since the query
> doesn't seem to follow the natural hierarchal structure? And if so, can
> indexes be modified or added to enhance performance in a flexible way?

All data in XDb is indexed. Specifically instances of each class are indexed. User cannot modify/add indexes.

> An example of how the query would be manifested in Xdb would be great!

An extended example is being developed and will be posted at www.xdb1.com/Example/Ex046.asp Received on Thu Jan 10 2002 - 00:18:55 CET